bound_awgn_r12_k3_hard.m

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% Name: bound_AWGN_conv_R12_K3_hard.m
% Date: October 19, 2005
% Description:
% Bound for a binary K=3 rate-1/2 convolutional code with hard-decision
% Viterbi decoding with binary modulation over an AWGN channel.
%
% Copyright (c) 2005. Robert Morelos-Zaragoza. All rights reserved.

clear
rate=1/2;
SNRinit = 0;
SNRinc = 1;
SNRfinal = 10;
SNR = [];
Pb = [];
Pbvit = [];

for SNRdB = SNRinit:SNRinc:SNRfinal 
    EsN0 = rate*(10.^(SNRdB/10));
    p = Q(sqrt(2*EsN0));
    x = sqrt(4*p*(1-p));
    Pb1 = (((1+x)/2) * x^5/((1-2*x)^2)) + (((1-x)/2) * -x^5/((1+2*x)^2));
    Pb2 = x^5/((1-2*x)^2);
    Pb = [Pb Pb1];
    Pbvit = [Pbvit Pb2];
    SNR = [SNR SNRdB];
end

semilogy (SNR,Pb,'-rs');
hold on
%semilogy (SNR,Pbvit,'-ro');